The exchange of produce by banking and transportation is a branch of this type of living. The vaisyas are divided into many subsections: some of them are called ksetri, or landowners, some are called krsana, or land tillers, some of them are called tila-vanik, or grain raisers, some are called gandha-vanik, or merchants in spices, and some are called suvarna-vanik, or merchants in gold and banking. The brahmanas are the teachers and spiritual masters, the ksatriyas protect the citizens from the hands of thieves and miscreants, and the vaisyas are in charge of production and distribution. The sudras, the unintelligent class of men who cannot act independently in any of the above-mentioned activities, are meant for serving the three higher classes for their livelihood.

Formerly, the brahmanas were given all the necessities of life by the ksatriyas and vaisyas because they had no time to spend making a living. The ksatriyas would collect taxes from the vaisyas and sudras, but the brahmanas were exempt from paying income tax or land revenue. That system of human society was so nice that there were no political, social and economic upheavals. The different castes, or varna classifications, are therefore essential for maintaining a peaceful human society.